Files
linux/fs/ceph
Max Kellermann 249e0a47cd ceph: fix crash after fscrypt_encrypt_pagecache_blocks() error
The function move_dirty_folio_in_page_array() was created by commit
ce80b76dd3 ("ceph: introduce ceph_process_folio_batch() method") by
moving code from ceph_writepages_start() to this function.

This new function is supposed to return an error code which is checked
by the caller (now ceph_process_folio_batch()), and on error, the
caller invokes redirty_page_for_writepage() and then breaks from the
loop.

However, the refactoring commit has gone wrong, and it by accident, it
always returns 0 (= success) because it first NULLs the pointer and
then returns PTR_ERR(NULL) which is always 0.  This means errors are
silently ignored, leaving NULL entries in the page array, which may
later crash the kernel.

The simple solution is to call PTR_ERR() before clearing the pointer.

Cc: stable@vger.kernel.org
Fixes: ce80b76dd3 ("ceph: introduce ceph_process_folio_batch() method")
Link: https://lore.kernel.org/ceph-devel/aK4v548CId5GIKG1@swift.blarg.de/
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2025-09-09 12:57:03 +02:00
..
2023-11-03 23:28:34 +01:00
2025-04-04 11:31:42 -07:00
2023-08-22 09:01:48 +02:00
2022-03-01 18:26:37 +01:00
2025-06-10 22:21:16 -04:00